Combined effects of blood pressure and glucose status on the risk of chronic kidney disease.

This study aimed to assess the combined effects of blood pressure (BP) and glucose status on chronic kidney disease (CKD) incidence in young and middle-aged adults. We examined data from 1,297,341 Japanese individuals aged <60 years (60.1% men; mean age 41.4 ± 9.3 years) with no history of CKD at baseline. The interval-censored Cox proportional hazards model with covariates was used. During a median follow-up period of 2.1 years, new onset CKD (estimated glomerular filtration rate <60 ml/min/1.73 m2 and/or proteinuria) occurred in 80,187 participants. In participants without antihypertensive treatment (AHT), the adjusted hazard ratios (95% confidence interval) per 1-standard deviation, that is, 15 mmHg increase in systolic BP for CKD incidence, were 1.08 (1.07-1.09), 1.12 (1.10-1.13), and 1.15 (1.12-1.18) in normoglycemia, borderline glycemia, and diabetes groups, respectively. These ratios were significantly higher in the borderline glycemia and diabetes groups compared with those in the normoglycemia group (interaction p < 0.0001). The interaction between BP and borderline glycemia was evident when the outcome definition was restricted to proteinuria. In participants under AHT, systolic BP was most strongly associated with CKD risk in the diabetes group, although no significant interaction was observed. High BP and high glucose status may synergistically increase the incidence of CKD. Strict BP management may play an important role in the early prevention of CKD in individuals with worse glucose status within the young and middle-aged population. This large-scale longitudinal cohort study showed high BP and diabetes synergistically increased the risk of CKD in individuals without AHT. Strict BP management may play an important role in the early prevention of CKD in individuals with worse glucose status within the young and middle-aged population.

Sodium glucose cotransporter 2 inhibitor suppresses renal injury in rats with renal congestion.

Renal congestion is an issue of cardiorenal syndrome in patients with heart failure. Recent clinical and basic studies suggest a renoprotective potential of sodium-glucose cotransporter (SGLT) 2 inhibitors. However, the effect on renal congestion and its mechanism is not fully understood. Thus, we aimed to clarify the effect of SGLT inhibition in a renal congestion model. Renal congestion was induced in the left kidney of male Sprague-Dawley rats by ligation of the inferior vena cava between the renal veins. The SGLT2 inhibitor tofogliflozin or vehicle was orally administered daily from the day before IVC ligation until two days after surgery. On the third postoperative day, both the right control kidney and the left congested kidney were harvested and analyzed. Kidney weight and water content was increased, and renal injury and fibrosis were observed in the left congested kidney. Kidney weight gain and hydration were improved with tofogliflozin treatment. Additionally, this treatment effectively reduced renal injury and fibrosis, particularly in the renal cortex. SGLT2 expression was observed in the congested kidney, but suppressed in the damaged tubular cells. Molecules associated with inflammation were increased in the congested kidney and reversed by tofogliflozin treatment. Mitochondrial dysfunction provoked by renal congestion was also improved by tofogliflozin treatment. Tofogliflozin protects against renal damage induced by renal congestion. SGLT2 inhibitors could be a candidate strategy for renal impairment associated with heart failure.

NRIP1 regulates cell proliferation in lung adenocarcinoma cells.

Nuclear receptor interacting protein 1 (NRIP1) is a transcription cofactor that regulates the activity of nuclear receptors and transcription factors. Functional expression of NRIP1 has been identified in multiple cancers. However, the expression and function of NRIP1 in lung adenocarcinoma have remained unclear. Thus, we aimed to clarify the NRIP1 expression and its functions in lung adenocarcinoma cells. NRIP1 and Ki-67 were immunostained in the tissue microarray section consisting of 64 lung adenocarcinoma cases, and the association of NRIP1 immunoreactivity with clinical phenotypes was examined. Survival analysis was performed in lung adenocarcinoma data from The Cancer Genome Atlas (TCGA). Human A549 lung adenocarcinoma cell line with an NRIP1-silencing technique was used in vitro study. Forty-three of 64 cases were immunostained with NRIP1. Ki-67-positive cases were more frequent in NRIP1-positive cases as opposed to NRIP1-negative cases. Higher NRIP1 mRNA expression was associated with poor prognosis in the TCGA lung adenocarcinoma data. NRIP1 was mainly located in the nucleus of A549 cells. NRIP1 silencing significantly reduced the number of living cells, suppressed cell proliferation, and induced apoptosis. These results suggest that NRIP1 participates in the progression and development of lung adenocarcinoma. Targeting NRIP1 may be a possible therapeutic strategy against lung adenocarcinoma.

Case Report: A case of TAFRO syndrome with severe and prolonged thrombocytopenia: diagnostic pitfalls.

Thrombocytopenia, anasarca, myelofibrosis, renal dysfunction, and organomegaly (TAFRO) syndrome is a rare condition with diverse clinical and pathological characteristics related to multi-organ damage. We report a case of TAFRO syndrome complicated by immune thrombocytopenia with prolonged fever and thrombocytopenia for several weeks. A 61-year-old man was transferred with sepsis caused by Enterococcus faecalis, and developed disseminated intravascular coagulation. Antibiotics treatment was initiated: however, low-grade fever and thrombocytopenia persisted despite the adequate antimicrobial treatment. Systemic edema, pleural effusion, and ascites had developed before hospitalization, and renal and liver function had deteriorated, resulting in progressive multi-organ damage. Prednisolone 40 mg/day was initiated based on the assumption of a condition in which excessive production of inflammatory cytokines would lead to systemic deterioration and fatal organ damage. Subsequently, the fever resolved, and renal function began to normalize. However, thrombocytopenia did not show much recovery trend after Helicobacter pylori eradication therapy and initiation of thrombopoietin receptor agonists. Bone marrow biopsy results showed normal bone marrow with no malignant findings. Alternatively, significant clinical signs met the diagnostic criteria for TAFRO syndrome, and a renal biopsy revealed thrombotic microangiopathy, which is also reasonable for renal involvement in TAFRO syndrome. The use of cyclosporine remarkably corrected the thrombocytopenia. We considered this a case of TAFRO syndrome that developed after sepsis with disseminated intravascular coagulation and performed the differential diagnosis of prolonged thrombocytopenia and excluded it. Although TAFRO syndrome is a unique disease concept, diagnostic criteria may consist of nonspecific elements such as generalized edema, thrombocytopenia, persistent fever, and elevated inflammatory response, and there are many differential conditions to exclude, requiring caution in diagnosing TAFRO syndrome.

Pericyte detachment and renal congestion involve interstitial injury and fibrosis in Dahl salt-sensitive rats and humans with heart failure.

Congestive heart failure produces fluid volume overload, central and renal venous pressure elevation, and consequently renal congestion, which results in worsening renal function. Pericyte detachment and pericyte-myofibroblast transition (PMT) were linked to renal interstitial fibrosis. Dahl salt-sensitive hypertensive (DahlS) rats are a non-surgical renal congestion model. The relation, however, between renal interstitial damage, pericyte morphology, and PMT in the renal congestion of DahlS rats has not been reported. DahlS rats (8-week-old) were fed normal salt (NS, 0.4% NaCl) or high salt (HS, 4% NaCl), and the left kidney was decapsulated to reduce renal interstitial hydrostatic pressure (RIHP) at 9 weeks old. One week after capsulotomy, both kidneys were analyzed by molecular and histological techniques. Renal pericyte structure was assessed in the body donors with/without venous stasis. Markers of tubulointerstitial damage, interstitial fibrosis, and PMT were upregulated in the right non-decapsulated kidney of DahlS rats fed HS. Renal tubular injury and fibrosis were detected in the HS diet groups in histological analysis. Pericyte detachment was observed in the right non-decapsulated kidney of DahlS rats fed HS by low vacuum-scanning electron microscopy. Decapsulation in DahlS rats fed HS attenuated these findings. Also, renal pericytes detached from the vascular wall in patients with heart failure. These results suggest that pericyte detachment and PMT induced by increased RIHP are responsible for tubulointerstitial injury and fibrosis in DahlS rats and humans with renal congestion. Renal venous congestion and subsequent physiological changes could be therapeutic targets for renal damage in cardiorenal syndrome.

Sodium-glucose cotransporter-2 inhibitors increase urinary tract infections?-a cross sectional analysis of a nationwide Japanese claims database.

Sodium-glucose cotransporter-2 (SGLT2) inhibitors are a novel class of antidiabetic drugs. Guidelines for the proper use of SGLT2 inhibitors recommend caution regarding urinary tract infections (UTIs). However, little evidence has been reported on the relationship between SGLT2 inhibitors and UTIs in large epidemiological studies. We investigated (1) the relationship between diabetes mellitus (DM) and UTIs and (2) the relationship between SGLT2 inhibitor prescriptions and the likelihood of developing UTIs in patients with DM, using a nationwide Japanese health insurance claims database by MDV analyzer®. We found that the incidence of UTIs was significantly higher among patients with DM than among those without DM (odds ratio (OR), 1.71; 95% confidence interval (CI), 1.69-1.72, for male; OR, 1.90; 95% CI, 1.89-1.92 for female). In contrast, in male patients with DM, the prescription of SGLT2 inhibitors was negatively associated with the likelihood of developing UTIs (OR, 0.74; 95% CI, 0.72-0.75). Among female patients with DM, there was no significant difference in the incidence of UTIs with or without an SGLT2 inhibitor prescription (OR, 0.99; 95% CI, 0.96-1.01). Subgroup analyses by age confirmed similar relationships between SGLT2 inhibitor prescriptions and UTIs, except for female patients aged ≤39 years, in whom SGLT2 inhibitor prescription was negatively associated with the likelihood of developing UTIs. In conclusion, our analysis of a nationwide claims database found no evidence that SGLT2 inhibitors increase UTIs in Japanese patients with DM, regardless of sex or age.

Cross-classification by systolic and diastolic blood pressure levels and chronic kidney disease, proteinuria, or kidney function decline.

Predicting and preventing new-onset chronic kidney disease (CKD) through blood pressure (BP) measurements is worthwhile. This study assessed the risk of CKD, which was defined as proteinuria and/or an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2, according to cross-classification by systolic and diastolic BP (SBP and DBP). This retrospective population-based cohort study analyzed data from 1,492,291 participants without CKD and without antihypertensive treatment in the JMDC database, which contains the annual health check-up data of Japanese aged <75 years. During a mean follow-up of 3.2 years, CKD incidence, proteinuria, and eGFR <60 mL/min/1.73 m2 occurred in 92,587, 67,021, and 28,858 participants, respectively. When the SBP/DBP <120/<80 mmHg group was set as a reference, both high SBP and DBP were significantly associated with an elevated CKD risk. DBP tended to be more strongly associated with CKD risk than SBP; the hazard ratio of CKD was 1.44-1.80 in the group with SBP/DBP of 130-139/≥90 mmHg and 1.23-1.47 in the group with SBP/DBP of ≥140/80-89 mmHg. A similar result was observed for developing proteinuria and eGFR <60 mL/min/1.73 m2. SBP/DBP ≥150/<80 mmHg was strongly associated with an elevated CKD risk due to the increased risk of eGFR decline. High BP, especially isolated high DBP levels, is a significant risk factor for CKD among individuals around middle age without kidney disease. Moreover, attention should be paid to kidney function, particularly eGFR decline, in the case of low DBP with extremely high SBP levels.

MPO-ANCA-positive conversion and microscopic polyangiitis development in idiopathic interstitial pneumonia: a case report.

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis is a systemic autoimmune disease characterized by necrotizing inflammation of the small blood vessels. ANCA-associated vasculitis is subclassified into three variants: granulomatosis with polyangiitis, eosinophilic granulomatosis with polyangiitis, and microscopic polyangiitis (MPA). Myeloperoxidase (MPO) ANCA is a marker antibody for MPA. Interstitial pneumonia (IP) is occasionally complicated with MPA. However, only a few cases of idiopathic IP develop MPO-ANCA-positive conversion and MPA. Therefore, we present a case of a 70-year-old Japanese man with idiopathic IP who developed MPO-ANCA-positive conversion and MPA. We performed renal biopsy, which revealed pauci-immune crescentic glomerulonephritis. The patient was treated with intravenous methylprednisolone pulse therapy and oral prednisone, and the patient's laboratory data gradually improved with steroid therapy. The association between the production of MPO-ANCA and IP remains unclear, and the present case suggests that IP plays a role in inducing MPO-ANCA production. Patients with idiopathic IP should be followed-up carefully for an examination of increased MPO-ANCA levels and MPA development. In addition, early gastric cancer was detected during upper gastrointestinal endoscopy in our case, and it could also be important not to miss malignancy in patients with ANCA-associated vasculitis.

Association Between Ambulatory Blood Pressure and Risk of Home Hypertension in a Normotensive Population: The Ohasama Study.

BACKGROUND: We investigated the association between ambulatory blood pressure (BP) and the risk of home hypertension in a normotensive population and whether considering ambulatory BP improves the 10-year prediction model for home hypertension risk, which was developed in the previous Ohasama Study. METHODS: In this prospective study, we followed up with 410 participants (83.2% women; age, 53.6 years) without a home and ambulatory hypertension in the general population of Ohasama, Japan. The Cox model was used to assess the hazard ratios (HRs) for home hypertension (home BP ≥ 135/≥85 mmHg or the initiation of antihypertensive treatment) and model improvement. RESULTS: During a mean 14.2-year follow-up, 225 home hypertension incidences occurred. The HR (95% confidence interval) for home hypertension incidence per 1-SD higher (=6.76 mmHg) 24-hour systolic BP (SBP) was 1.59 (1.33 to 1.90), after adjustments for possible confounding factors, including baseline home SBP. Harrell's C-statistics increased from 0.72 to 0.73 (P = 0.11) when 24-hour SBP was added to the basic 10-year home hypertension prediction model, which includes sex, age, body mass index, smoking status, office SBP, and baseline home SBP. Continuous net reclassification improvement (0.53, P < 0.0001) and integrated discrimination improvement (0.028, P = 0.0014) revealed improvement in the model. CONCLUSIONS: A total of 24-hour SBP could be an independent predictor of future home hypertension. Home BP and 24-hour BP can longitudinally influence each other in the long term.

Inhibition of sodium-glucose cotransporter 2 suppresses renal stone formation.

BACKGROUND AND AIMS: Nephrolithiasis is a common renal disease with no effective medication. Sodium-glucose cotransporter-2 (SGLT2) inhibitors, an anti-diabetic agent, have diuretic and anti-inflammatory properties and could prevent nephrolithiasis. Here, we investigated the potential of SGLT2 inhibition against nephrolithiasis using large-scale epidemiological data, animal models, and cell culture experiments. METHODS: This study included the data of diabetic patients (n = 1,538,198) available in the Japanese administrative database and divided them according to SGLT2 inhibitor prescription status. For animal experiments, renal calcium oxalate stones were induced by ethylene glycol in Sprague-Dawley rats, and phlorizin, an SGLT1/2 inhibitor, was used for the treatment. The effects of SGLT2-specific inhibition for renal stone formation were assessed in SGLT2-deficient mice and a human proximal tubular cell line, HK-2. RESULTS: Nephrolithiasis prevalence in diabetic men was significantly lower in the SGLT2 inhibitor prescription group than in the non-SGLT2 inhibitor prescription group. Phlorizin attenuated renal stone formation and downregulated the kidney injury molecule 1 (Kim1) and osteopontin (Opn) expression in rats, with unchanged water intake and urine volume. It suppressed inflammation and macrophage marker expression, suggesting the role of the SGLT2 inhibitor in reducing inflammation. SGLT2-deficient mice were resistant to glyoxylic acid-induced calcium oxalate stone formation with reduced Opn expression and renal damages. High glucose-induced upregulation of OPN and CD44 and cell surface adhesion of calcium oxalate reduced upon SGLT2-silencing in HK-2 cells. CONCLUSION: Overall, our findings identified that SGLT2 inhibition prevents renal stone formation and may be a promising therapeutic approach against nephrolithiasis.

(Pro)renin receptor and insulin signalling regulate cell proliferation in MCF-7 breast cancer cells.

(Pro)renin receptor [(P)RR] is related to both the renin-angiotensin system and V-ATPase with various functions including stimulation of cell proliferation. (P)RR is implicated in the pathophysiology of diabetes mellitus and cancer. Hyperinsulinemia is observed in obesity-related breast cancer. However, the relationship between (P)RR and insulin has not been clarified. We have therefore studied the effect of insulin on (P)RR expression, cell viability and AKT phosphorylation under the conditions with and without (P)RR knockdown. Effects of insulin were studied in a human breast cancer cell line, MCF-7. Cell proliferation assay was performed by WST-8 assay. (P)RR expression was suppressed by (P)RR-specific siRNAs. The treated cells were analysed by western blotting and reverse transcriptase-quantitative polymerase chain reaction analysis. Insulin stimulated proliferation of MCF-7 cells and increased (P)RR protein expression, but not (P)RR mRNA levels. Moreover, autophagy flux was suppressed by insulin. Suppression of (P)RR expression reduced cell number of MCF-7 cells and AKT phosphorylation significantly in both the presence and the absence of insulin, indicating that (P)RR is important for cell viability and AKT phosphorylation. In conclusion, insulin upregulates the level of (P)RR protein, which is important for cell viability, proliferation, AKT phosphorylation and autophagy in breast cancer cells.

Inhibition of platelet-derived growth factor pathway suppresses tubulointerstitial injury in renal congestion.

OBJECTIVE: Increased central venous pressure in congestive heart failure is responsible for renal dysfunction, which is mediated by renal venous congestion. Pericyte detachment from capillaries after renal congestion might trigger renal fibrogenesis via pericyte-myofibroblast transition (PMT). Platelet-derived growth factor receptors (PDGFRs), which are PMT indicators, were upregulated in our recently established renal congestion model. This study was designed to determine whether inhibition of the PDGFR pathway could suppress tubulointerstitial injury after renal congestion. METHODS: The inferior vena cava between the renal veins was ligated in male Sprague-Dawley rats, inducing congestion only in the left kidney. Imatinib mesylate or vehicle were injected intraperitoneally daily from 1 day before the operation. Three days after the surgery, the effect of imatinib was assessed by physiological, morphological and molecular methods. The inhibition of PDGFRs against transforming growth factor-ß1 (TGFB1)-induced fibrosis was also tested in human pericyte cell culture. RESULTS: Increased kidney weight and renal fibrosis were observed in the congested kidneys. Upstream inferior vena cava (IVC) pressure immediately increased to around 20 mmHg after IVC ligation in both the imatinib and saline groups. Although vasa recta dilatation and pericyte detachment under renal congestion were maintained, imatinib ameliorated the increased kidney weight and suppressed renal fibrosis around the vasa recta. TGFB1-induced elevation of fibrosis markers in human pericytes was suppressed by PDGFR inhibitors at the transcriptional level. CONCLUSION: The activation of the PDGFR pathway after renal congestion was responsible for renal congestion-induced fibrosis. This mechanism could be a candidate therapeutic target for renoprotection against renal congestion-induced tubulointerstitial injury.

Actual impact of angiotensin II receptor blocker or calcium channel blocker monotherapy on renal function in real-world patients.

OBJECTIVE: This observational retrospective cohort study investigates the effect of antihypertensive therapy with angiotensin II receptor blockers (ARBs) or dihydropyridine calcium channel blockers (dCCBs) monotherapy on renal function using longitudinal real-world health data of a drug-naive, hypertensive population without kidney disease. METHODS: Using propensity score matching, we selected untreated hypertensive participants ( n  = 10 151) and dCCB ( n  = 5078) or ARB ( n  = 5073) new-users based on annual health check-ups and claims between 2008 and 2020. Participants were divided by the first prescribed drug. RESULTS: The mean age was 51 years, 79% were men and the mean estimated glomerular filtration rate (eGFR) was 78 ml/min per 1.73 m 2 . Blood pressure rapidly decreased by approximately 10% in both treatment groups. At the 1-year visit, eGFR levels decreased in the ARB group by nearly 2% but increased in the dCCB group by less than 1%. However, no significant difference was apparent in the annual eGFR change after the 1-year visit. The risk for composite kidney outcome (new-onset proteinuria or eGFR decline ≥30%) was lowest in the ARB group owing to their robust effect on preventing proteinuria: hazard ratio (95% confidence interval) for proteinuria was 0.91 (0.78-1.05) for the dCCB group and 0.54 (0.44-0.65) for the ARB group, compared with that for the untreated group after ending follow-up at the last visit before changing antihypertensive treatment. CONCLUSION: From the present findings based on the real-world data, ARBs can be recommended for kidney protection even in a primary care setting. Meanwhile, dCCB treatment initially increases eGFR with no adverse effects on proteinuria.

Methylglyoxal Induces Inflammation, Metabolic Modulation and Oxidative Stress in Myoblast Cells.

Uremic sarcopenia is a serious clinical problem associated with physical disability and increased morbidity and mortality. Methylglyoxal (MG) is a highly reactive, dicarbonyl uremic toxin that accumulates in the circulatory system in patients with chronic kidney disease (CKD) and is related to the pathology of uremic sarcopenia. The pathophysiology of uremic sarcopenia is multifactorial; however, the details remain unknown. We investigated the mechanisms of MG-induced muscle atrophy using mouse myoblast C2C12 cells, focusing on intracellular metabolism and mitochondrial injury. We found that one of the causative pathological mechanisms of uremic sarcopenia is metabolic flow change to fatty acid synthesis with MG-induced ATP shortage in myoblasts. Evaluation of cell viability revealed that MG showed toxic effects only in myoblast cells, but not in myotube cells. Expression of mRNA or protein analysis revealed that MG induces muscle atrophy, inflammation, fibrosis, and oxidative stress in myoblast cells. Target metabolomics revealed that MG induces metabolic alterations, such as a reduction in tricarboxylic acid cycle metabolites. In addition, MG induces mitochondrial morphological abnormalities in myoblasts. These changes resulted in the reduction of ATP derived from the mitochondria of myoblast cells. Our results indicate that MG is a pathogenic factor in sarcopenia in CKD.